Cornicabra virgin olive oil: a study of five crop seasons. Composition, quality and oxidative stability

Abstract

The chemical composition of Cornicabra virgin olive oils (n=181) from five successive crop seasons (from 1994/95 to 1998/99) and its relationship with quality and oxidative stability is examined. The main characteristics of Cornicabra olive oils were: a high oleic acid (80.4±1.0%, as mean and standard deviation) and low linoleic acid content (4.5±0.6%); high campesterol level (4.2±0.2%), exceeding the EU Regulation upper limit of 4%; large total phenol content (ranging from 19 to 380 mg/kg as caffeic acid for the commercial oils, and from 180 to 614 mg/kg for the Abencor oils), and oxidative stability ranging from 9 to 143 h, by Rancimat, for the commercial oils and from 18 to 193 h for the Abencor oils. Sensory evaluation showed that the total score of 35% of commercial Cornicabra olive oil was lower than the limit of 6.5 established for the ‘extra-virgin’ category, whereas the minimum score observed for Abencor oils was 6.8. This means that, although the majority of the chemical parameters fell within the limits established for the maximum olive oil category, with a few exceptions, significantly more of these olive oils fail the sensory minimum requirements for the highest category.